Press control mechanism



July 6, 1937.- HYDE 2,086,268

PRESS CONTROL MECHANISM -Filed.Jan. 11, 1936 Patented 7 July 6, 1937 UNITED STAT mass conrnor. MECHANISM Elbert L. Hyde, Shaker Heights, Ohio, assignor to The American Laundry Machinery Company, Norwood, Ohio. Application January 11,

7 Claims.

This invention relates to improvements in control mechanism for pressing machines.

Anobject of the present invention is the provision of control means for a pressing machine so arranged that the pressing machine cannot be operated except when the pressing members are at a desired temperature which is neither too hot nor to cold to produce the desired pressing operation. Another object of the invention is to provide a control mechanism fora pressing machine having a pair of coacting pressing elements which provides means for disabling the press operating mechanism unless one or both of the pressmg members is heated to a point within a predetermined temperature range.

Other objects and advantages oi. the present invention involve the provision of suitable control circuits for a press operating mechanism to provide the advantages above pointed out and the novel features of which will be pointed out in the appended claims.

In the drawing, Fig. 1 is an end elevation partly in section of a pressing machine embodying my invention with my improved control mechanism shown diagrammatically; Fig. 2 is fragmental enlarged sectional view through one of the pressing members of Fig. 1; Fig. 3 is a view taken along the line 3-3 of Fig. 2; Fig. 4 is a diagram of a portion of the control circuit of Figs. 1, 2 and 3; while Fig. 51s a diagrammatic layout of a modified form 0!. press control mechanism.

In certain pressing machine operations it is desirable that the temperature of one or both of a pair of coacting pressing members be ac-' curately controlled and it is also desirable to render the press operation impossible unless the pressing member or members are at the desired 4o temperature. This necessity for closely con-- trolled temperatures arises under various circum-- stances. For instance, in the production of. starchless collars, layers of fabric arecementedtogether by the use of a cellulose'derivative and a solvent or softener for this derivative. when the parts are arranged in suitable layers the entire assembly is then subjected to heat .and pressure to cement the fabric layers together. In this operationclose control of the temperature of the pressing members is, necessary to produce the highest quality of work. It is desirable that the pressing members be neither too hot nor too cold and it is often desirable that a certain specified relationship'be maintained be-- 55 tween the two coacting pressing members, such a corporation of Ohio 1930, Serial No. 58,684

for instance as maintaining one oi these members at a slightly higher temperature than the other.

It is also against the operation of a pressing machine wherein one or both of the pressing members'is too hot but it is also desirable that the machine be not operated ii thepressing members are too cold as the work .thus turned out is of a low quality.

My impr'oved control mechanism insures that a pressing machine cannot be operated unless one or both of the pressing members is heated to a predetermined temperature, that is tosay, that it is above a certain temperature and below a certain other temperature.

The machine shown for illustrative purposes comprises a frame In supporting a stationary pressing bed II which may be heated by a suitable heating fluid supplied at l2. Pivotally mounted on the frame is a head lever ii for carrying a pressing head It into and out of pressing engagementwith thebed II. The head it desirable in some cases to gu'ard I maybe supplied with heating fluid at It. A pair of toggles I6 is provided for causing suitable movement of the pressing head and these toggles are biased in broken position by the spring.

I! which normally maintains the press open. A cylinder and piston motor I! is provided for straightening the 'toggles and carrying out a pressing operation. Motive fluid for motor l8 is supplied through conduit i9, valve 20, conduit 2!, valve casing 22 and supply conduit 23. The

valve 20 is a conventional representation of a valve which will stay in either ,open or closed position salt is moved by manipulation of manual 20a. with the press open the movable valve member is in the position shown in Fig. '1 which closes the inlet conduit and opens. the motor l8 to'exhaust through the port 20b. Valve casing 22 houses a normally closed. inlet va1ve22a biased to that position by a spring 22b and-having a stem 22c which forms part of or is operatively connected with the core of a solenoid whose winding is represented at 24.

In the form shown, valve 22a normally prevents operation of the pressgcontrol mechanism by cutting off the ope ting fluid for motor It. To render the press one ting mechanism effective it is necessary to supply electricity to the solenoid winding, 24 to move valve 22a to its open position against the action of spring 22b. I provide an energizing circuit for this solenoid winding which is responsive-to the temperature of one or both of the pressing members Ii and I4 so. that the solenoid winding is energized only within a predetermined'range of temperature. To this end I place a thermostatic element 25 in a position to be readily affected by the temperature of the pressing member A suitable form of this thermostatic element is shown in Figs. 2 and 3 which comprises a casing 26in intimate contact with the casting of the pressing bed H and surrounded preferably by heat insulating material 21 so as'to prevent any effect.

' connected to a bimetallic bar '29 which is adapted to make contact at 30 with an adjustable contact 3| which in turn is connected by a lead wire 32 with another adjustable contact 33 adapted to close a circuit at 34 with a bimetallic bar 35 which in turn is connected to the outgoing lead 36. The current carrying parts are suitably insulated from the pressing machine and thebimetallic elements 29 and 35 may be formed of dissimilar metals secured together in a well known manner. These elements are now provided in a form which renders them very sensitive to slight changes in temperature so that they are operativewithin one or two degrees to closely control the range of temperature. In the form shown the thermostatic element 29 preferably makes contact at a predetermined low temperature and the thermostatic element 35 is adapted to break contact at a predetermined high temperature so that within the normal operating range of the pressing member both contacts are closed. It will be obvious that with this connection for energizing the solenoid 24 that within the predetermined range of temperature the solenoid would be energized to hold valve 22a open and to permit operation of the pressing machine. Such a use of my device is possible but Figs. 1 and 4 illustrate a further. carrying out of my idea by providing similar thermostatic elements on both of the pressing members II and H. In other words, the thermostatic element 3'! on the pressing head is similar in all respects to themember25 on the pressing bed and the two are connected in series by wire 36. In the diagraniin Fig. 4 the parts of the thermostatic element .31 are given similar reference numerals to those in thermostatic element 25 with the addition of the suffix a. The complete electrical operating circuit is then by way of L1, 23. 29, 32, 35, 36, 29a, 32a, 35a, 38, 24,'Lz.

With the arrangement shown, the contacts 3| and 33 would be set forthe predetermined low and high temperature points desired in the pressing bed and the similar contacts for the pressing head would be adjusted to thesame or different Then, upon heattemperatures desired there. ing up the pressing members, when the members reached thepredetermined low temperature contact would be made between 30 and 3| on the pressing bed and the similar contacts on the pressing head. Inasmuch as the contacts 33 and 34 on the pressing bedfand the similar contacts on the pressing head would be closed at the low temperature ,due to the construction of the thermostat, the solenoid 24 would then be energized by thecircuit above set forth, valve 22a would be held open-and the press would be operated by manipulation of manual 20:: by the operator. If one or the other of the pressing members became too hot, thermostatic element 35 or 35a would break thecircuit. If either of the pressing elements became too cold, thermostatic element 29 or 29a would break the circuit. The press is thus disabled except when both of the pressing members are within a predetermined range of temperature which may be set as closely as desired.

While I have shown a circuit in which the,

valve 22a is normally in closed position, it will be obvious to those skilled in this art that this valve mightnormally be held open and move to closed position by the supply of electrical energy to solenoid 24 when the pressing element or elements dropped below a certain temperature or rose above a certain temperature. This is only a reversal of the operation just described and I prefer the form shown because if the electric circuit fails, valve 22a will close and the press cannot be operated until the electrical system is re-established.

A modification is shown in Fig. 5 wherein 40 represents a pressing element of a pressing machine and 4| represents an operating motor functioning similar to motor IE to close the press which would normally be biased in open position. Motive fluid is supplied to motor 4| through conduit 42, valve casing 43 and supply conduit 44 which provides high pressure fiuid.-

tion to valve 20 above described and is controlled by manipulation of the manual 41a.

In this modification the thermostatic element is a Bourdon tube 5| in heat receiving relationship with the pressing member with which'it is associated. This tube has a fixed end 5|a and a movable end 5; connected by rod 52 to the valve in casing 49. This valve is a piston valve 49a. having a passage 4% which provides communication between conduits 50 and 48 only when the position of the Bourdon tube is that corresponding to the desired temperature of the pressing member. Fig. 5 shows the position of the parts when the pressing member is within the operating temperature range. If the pressing member becomes colder the Bourdon tube will contract and valve 49a will move to the right and cut oil communication between conduits 50 and 48. If the temperature of the pressing member rises the Bourdon tube will expand and valve 49a will move to the left and also cut oil communication between conduits 50 and 48. In either of these cases manipulation of manual 41a will be inefiective to provide pressoperatlon as a more sensitive operation of the thermostatically controlled valve 490.

The only purpose in providing a lower pressure in the control circuit 50, 48, 46 is to achieve a. more sensitive operation of the thermostatically controlled valve 49a.

It will be obvious/witlfiut ilustration that both of the COaCtBIK pressing members of a pressing machine may be provided with the Bourdon tube and piston valve 49a as illustrated in Fig. 5, the two valves being arranged in series to control the flow of fluid to conduit 48. This would be analogous to the electrical circuit of Fig. 4 and arranged so that if either of the pressing elements became too hot or too cold the control circuit would be deenergized and it would be im- 5 possible to operate the press. As in the first described form, the Bourdon tube and valve controlled thereby on the head might be set for a diilerent range of temperature than that on the bed.

- What I claim is:

tuation of said operating means. at such temperature or at lower temperatures. 20 2. In a pressing machine, a pair of coacting relatively movable pressing members operating means therefor, means i'or heating at least one of said pressing members, and control means forsaid operating means esponsive -.to a pre- 25 determined high temperat e and to a predetermined low temperature of said heated pressing member, said control means being arranged to render said operating means effective only between said predetermined temperatures. 0 3. In a' pressing machine, apair oi coasting relatively movable pressing members, operating means therefor, meansfor heating said members, and control means for disabling said op- M erating means responsive to a predetermined low temperature of either of said pressing members.

4. In a pressing machine, a pair of coacting relatively movable pressing members, operating means therefor, means for heating said mem- 40 bers, and control means for disabling said operating means upon either of said pressing members reaching a predetermined high temperature or a predetermined low temperature.

5. In a pressing machine, a pair .of coasting relatively movable pressing members, operating means therefor, means for heatingat least one' oi. said pressing members, a control member for disabling said operating means and normalhr in disabling position, power means for moving said control member into enabling position,

a power supply for energizing said power means,

control means in said power supply, and thermostatically controlled means responsive to the 'temperature of saidheated member, said-last named means having an operative connection with said control means for ca ing operation oi'the latter in power suppl ng direction onlywithin a predetermined rang of temperature oi indisabling position, electrical power means for moving said control member into enablingposition, an electric circuit for energizing said power means, a pair of contacts operatively associated with said circuit "and adapted to open at a predetermined low temperature of said heated pressing member and to remain closed at higher temperatures, a pair 01' contacts operatively as,-

sociated withsaid circuit and adapted to open.

at a predetermined temperature of said heated pressing member higher than said low tempera:-

ture and to remain closed at lower temperatures, and. thermostatic means responsive to the temperature of said pressing member for clos-- ing and opening said contacts. 4

'1. In .a.,pressing machine, a pair of coacting relatively movable pressir'ig members, operating means therefor, controlling means-tor said operating means, means for heating at least one of said pressing members, and means responsive to the temperature of said heated pressing member for energizing said controlling means only within a predetermined temperature range.

' ELBERT L. HYDE. 

